This project continues to focus upon applications of linear algebra, matrix and vector space methods to problems in biology. Applications are heavily involved in compartmental analysis; linear control theory, and generalized kinetics. No small part of the project is devoted to meeting purely mathematical problems which arise on their proper abstract grounds. BIBLIOGRAPHIC REFERENCES: Hearon, J. Z.: Nonsingular solutions of TA - BT equals C. Linear Algebra and Appl. 16: 57-63. 1977. Hearon, J. Z.: Minimum polynomials and control in linear systems. J. Res. Nat. Bur. Standards, 1977 (in press).